Percussion drill bits are used in downhole drilling applications to percussively degrade a formation into which a drill string is boring. The object of this invention is to disclose a percussive drill bit which may allow the drill string to bore a straighter hole and which may last longer than percussion drill bits of the prior art.
U.S. Pat. No. 5,947,215, which is herein incorporated by reference for all that it contains, discloses a rock drill bit for percussive drilling including a steel body in which six gauge buttons and a single front button are mounted. The gauge buttons are arranged symmetrically and equally spaced about a central axis of the bit. The front button is arranged along the central axis. The front button is of larger diameter than the gauge buttons are diamond-enhanced, and the front button may be diamond enhanced.
U.S. Pat. No. 4,304,312, which is herein incorporated by reference for all that it contains, discloses a percussion drill bit comprising a bit body including a shaft having a conical mounting portion to be mated with a conical mounting portion of a drill rod by means of substantially longitudinal friction forces. An annular row of circumferentially spaced button inserts extend from a front face of the body. A central button insert is disposed centrally of the other inserts and extends axially from the front face of the body beyond the other inserts to define a pilot insert.